Climate variability contributes significantly to poverty and food insecurity. Proactive approaches to managing climate variability within vulnerable rural communities and among institutions operating at community, sub-national, and national levels is a crucial step toward achieving the Millennium Development Goal of eradicating extreme poverty and hunger. Climate variability can impact a household's access to food by affecting subsistence production, income from primary production, local food prices, and sometimes the economy of an entire region. The risk of household food insecurity is determined by the success of livelihood strategies in the face of climate and other shocks. Across the economy, climate variability affects food security through its influence on investment, adoption of agricultural technology, aggregate production, market prices and economic development, and hence the ability of individuals, communities and nations to produce and purchase food. The impacts of climate variability are both ex post – losses that follow a climate shock — and ex ante — opportunity costs of conservative risk management responses to climatic uncertainty. The report summarizes the scientific basis, current methodology, and prospects for improving climate prediction at a seasonal time scale. Current forecast methods give modest to moderately-high prediction skill in "hunger hotspots" in East, West and Southern Africa, and other regions in the tropics and subtropics. Applications of climate information contribute to a comprehensive strategy to combat hunger. First is the use of seasonal climate prediction in early warning systems to guide interventions to avert food crises. Second is the use of climate information to manage risk in agricultural systems within vulnerable rural communities and among a range of institutions. This includes smallholder farmers who comprise the largest group of poor and food-insecure; intermediary institutions that interface with farmers, and can provide the information, technical guidance and production inputs required for effective climate risk management; and institutions that make climate-sensitive decisions at a broader scale that influence food security. We also discuss measures to strengthen institutional capacity and coordination to improve management of climate variability. Improved management of climate variability has appealing synergies with other interventions that target hunger, including soil fertility management, small-scale water management, markets, and extension and communication systems.